This invention is concerned with transferring articles of glassware from a blow station to conveyor means. In particular, the invention is concerned with a glassware handling system for transferring formed articles of glassware from a blow station of a glassware forming machine to conveyor means and with a method of transferring successively-formed articles of glassware from a blow station of a glassware forming machine to conveyor means.
In a conventional glassware forming machine of the individual section type, a plurality of sections, each of which is an individual glassware forming unit, are arranged side-by-side to receive gobs of molten glass from a common source and to feed their output to a common conveyor which runs transversely of the sections. The sections each comprise a blank station at which gobs of molten glass are formed into parisons by either a pressing or a blowing operation, a blow station at which parisons are blown into articles of glassware, and take-out means for transferring formed articles from the blow station to a dead plate from which the articles are pushed on to the conveyor.
The take-out means of a conventional machine comprises tongs operable to grip or release articles and means for moving the tongs between the blow station and the dead plate. The conveyor transfers the articles to a transfer wheel which transfers them to a lehr mat which transfers them into a lehr for annealing. The articles thus come into contact with the take-out tongs, the dead plate, the conveyor, the transfer wheel, and the lehr mat. As each contact is a potential source of damage to the articles, the articles are contacted an undesirable number of times.
In U.K. Patent Specification No. 1598539 (U.S. Pat. No. 4,244,725), there is described a glassware handling system for transferring formed articles of glassware from a blow station of a glassware forming machine to a lehr mat. This system involves less contacts with the articles than the conventional system described above and, furthermore, is more readily able to cope with higher production rates which may be achieved, for example, by using a machine as described in U.K. Patent Specification No. 1491859 (U.S. Pat. No. 3,914,120) in which an intermediate station is provided between the blank station and the blow station, the provision of this intermediate station allowing increased production. This glassware handling system comprises a carriage which is supported on horizontal guide rods which are supported above the lehr and the blow station. The carriage is movable along the guide rods transversely of the lehr and the blow station by operation of a piston and cylinder assembly. The carriage supports two horizontally-extending piston and cylinder assemblies each of which has a piston rod on which a head is mounted, the assemblies being operable to move the heads to positions above the blow station, above a lehr mat which enters the lehr, or above a dead plate located between the blow station and the lehr mat. Each head comprises one or more pairs of tongs for gripping and releasing articles of glassware and a vertically-extending piston and cylinder assembly operable to raise or lower the tongs.
In the operation of the glassware handling system described in U.K. Patent Specification No. 1598539, one of the heads is positioned above the blow station and the tongs thereof grip one or more articles of glassware, the head is then moved substantially horizontally to a position above the dead plate, the carriage is then moved horizontally to move this head away from the centre-line of the blow station and to move the other head on to the centre-line so that it can be moved to collect the next article or articles of glassware from the blow station, the first-mentioned head is then raised to bring articles supported thereby level with the lehr mat, the head is then positioned above the lehr mat and the tongs release the article or articles so that they are carried into the lehr by movement of the lehr mat.
The glassware handling system described in U.K. Patent Specification No. 1598539 has substantial advantages over the conventional system described above. For example, the articles are only handled by the tongs between the blow station and the lehr mat reducing the possibilities for damage to the articles, each machine section is truly independent and can be closed down, speeded up, or slowed down without effecting other sections, and the use of two heads allows increased cooling time and/or higher production. However, the system has the substantial disadvantage of reducing accessibility to the blow station. Whereas in the conventional system, the blow station can be reached by leaning across the conveyor and the dead plate, in the system described in U.K. Patent Specification No. 1598539, the lehr is in the way and access can only be obtained by climbing on top of the lehr and reaching across a portion of the lehr mat and the dead plate.
It is an object of the present invention to provide a glassware handling system which retains the advantages of the system described in U.K. Patent Specification No. 1598539 but gives improved access to the blow station.